1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2002 Richard Henderson 4 * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. 5 * Copyright (C) 2023 Luis Chamberlain <[email protected]> 6 * Copyright (C) 2024 Mike Rapoport IBM. 7 */ 8 9 #include <linux/mm.h> 10 #include <linux/vmalloc.h> 11 #include <linux/execmem.h> 12 #include <linux/moduleloader.h> 13 14 static struct execmem_info *execmem_info __ro_after_init; 15 16 static void *__execmem_alloc(struct execmem_range *range, size_t size) 17 { 18 unsigned long start = range->start; 19 unsigned long end = range->end; 20 unsigned int align = range->alignment; 21 pgprot_t pgprot = range->pgprot; 22 23 return __vmalloc_node_range(size, align, start, end, 24 GFP_KERNEL, pgprot, VM_FLUSH_RESET_PERMS, 25 NUMA_NO_NODE, __builtin_return_address(0)); 26 } 27 28 void *execmem_alloc(enum execmem_type type, size_t size) 29 { 30 struct execmem_range *range; 31 32 if (!execmem_info) 33 return module_alloc(size); 34 35 range = &execmem_info->ranges[type]; 36 37 return __execmem_alloc(range, size); 38 } 39 40 void execmem_free(void *ptr) 41 { 42 /* 43 * This memory may be RO, and freeing RO memory in an interrupt is not 44 * supported by vmalloc. 45 */ 46 WARN_ON(in_interrupt()); 47 vfree(ptr); 48 } 49 50 static bool execmem_validate(struct execmem_info *info) 51 { 52 struct execmem_range *r = &info->ranges[EXECMEM_DEFAULT]; 53 54 if (!r->alignment || !r->start || !r->end || !pgprot_val(r->pgprot)) { 55 pr_crit("Invalid parameters for execmem allocator, module loading will fail"); 56 return false; 57 } 58 59 return true; 60 } 61 62 static void execmem_init_missing(struct execmem_info *info) 63 { 64 struct execmem_range *default_range = &info->ranges[EXECMEM_DEFAULT]; 65 66 for (int i = EXECMEM_DEFAULT + 1; i < EXECMEM_TYPE_MAX; i++) { 67 struct execmem_range *r = &info->ranges[i]; 68 69 if (!r->start) { 70 r->pgprot = default_range->pgprot; 71 r->alignment = default_range->alignment; 72 r->start = default_range->start; 73 r->end = default_range->end; 74 } 75 } 76 } 77 78 struct execmem_info * __weak execmem_arch_setup(void) 79 { 80 return NULL; 81 } 82 83 void __init execmem_init(void) 84 { 85 struct execmem_info *info = execmem_arch_setup(); 86 87 if (!info || !execmem_validate(info)) 88 return; 89 90 execmem_init_missing(info); 91 92 execmem_info = info; 93 } 94